XML 169 R112.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
LONG-TERM DEBT - Convertible Notes (Details)
3 Months Ended
Mar. 11, 2015
USD ($)
$ / shares
Dec. 31, 2017
$ / shares
Dec. 31, 2019
USD ($)
Dec. 31, 2018
Mar. 31, 2015
$ / shares
Long-term debt          
Face amount of debt     $ 288,729,722    
Unamortized debt discount of notes     293,922    
4.50% Convertible Senior Notes due 2020          
Long-term debt          
Face amount of debt $ 75,000,000   $ 75,000,000    
Stated interest rate (as a percent)     4.50% 4.50%  
Debt instrument conversion ratio 0.0145136 0.0145515      
Conversion price per share | $ / shares $ 68.90 $ 68.11     $ 68.11
Sinking fund provided     $ 0    
Unamortized debt discount of notes $ 6,100,000   $ 293,000    
Debt discount, cash portion 2,600,000        
Debt discount, equity component $ 3,500,000